<!DOCTYPE html>
<html lang="en">
    <head>
        <meta charset="UTF-8">
        <title>Title</title>
        <link rel="stylesheet" href="bootstrap/css/bootstrap.min.css">
        <script src="jquery.min.js"></script>
        <script src="bootstrap/js/bootstrap.min.js"></script>
        <style>
            #chat{
                height: 400px;
            }
        </style>
    </head>
    <body>
        <button class="btn btn-primary" data-toggle="modal" data-target="#div_modal">
            打开模态框
        </button>
    <div class="modal" id="div_modal">
        <div class="modal-dialog">
            <div class="modal-content">
                <div class="modal-header">与...的聊天</div>
                <div id="chat" class="modal-body">内容</div>
                <div class="modal-footer">
                    <a class="<btn btn-warning" href="#">发送</a>
                </div>
            </div>
        </div>
    </div>
    </body>
</html>